The title compound, C13H12N4O3, is an imidazole derivative featuring an annealed purine ring system. The benzimidazole-inspired moiety is essentially planar (r.m.s. of all fitted non-H atoms = 0.0205 Å). An intramolecular O—H⋯N hydrogen bond occurs. In the crystal, intermolecular N—H⋯O and C—H⋯O hydrogen bonds are observed, which connect the molecules into chains along . The shortest centroid–centroid distance between two aromatic systems is 3.7771 (11) Å.